It was the closest you'll get to a YouTube moment in communist Cuba  and perhaps a harbinger of the postFidel Castro era. Earlier this month a video surfaced on the island showing a Havana university student, Eliecer Avila, peppering National Assembly leader Ricardo Alarcon with the kind of public questions that usually get Cubans tossed in jail. Why does a worker have to toil two or three days just to be able to buy a toothbrush? Avila, a computer science major, asked the visibly flummoxed Alarcon, who was visiting Avila's school outside Havana. Why can't Cubans freely travel abroad? Why don't they have access to the nice restaurants and hotels that only foreign tourists are allowed to enjoy?

What was most surprising about the interrogation was the fact that Avila got away with it. After initial reports that the young man had been detained for his effrontery, he appeared a week later on another video denying that he was jailed and insisting that his confrontation with Alarcon was meant "to build better socialism and not to destroy it." He added: "What needs to be fixed, what needs to be changed and revised, [we want to] do it within the revolution."

All of which indicates that the youthful outburst may not have been the spontaneous Havana Spring it was widely billed as, but rather a part of something quietly sanctioned by Cuba's interim President, Raul Castro. Since being tapped by his older brother, Fidel Castro, as the country's provisional leader in the summer of 2006 after Fidel underwent major intestinal surgery, Raul, 76, has pushed a more pragmatic, even reform-minded agenda that has encouraged limited public debate  and, just as important, worked to undermine hard-line fidelistas like Alarcon. The Avila episode was yet another sign of how firmly Raul seems to have consolidated his position  and why he's most likely to succeed his brother as full President this weekend in a National Assembly vote after Fidel officially resigned from the post today. "It wouldn't surprise me if people in Raul's faction leaked those [Avila] tapes out," says Brian Latell, a Cuba expert at the University of Miami and author of After Fidel.

Fidel's exit was hardly unexpected, and the streets of Havana today are reportedly calm. Seriously incapacitated by his stomach condition, the 81-year-old comandante, who has ruled Cuba and roiled the U.S. since taking power in 1959, has not been seen in public for a year and a half  even failing to appear at the podium last July 26 for the anniversary of the launching of his communist revolution. In December he released a letter saying he didn't want to "cling to power," which analysts like Latell called his de facto resignation. In his statement today, released in the wee hours of the morning to the government mouthpiece, Granma, Fidel acknowledged his deteriorating health and announced that while his "desire was always to complete my duty until my last breath...I will not aspire to nor accept  I repeat  I will not aspire to nor accept the office of President of the Council of State and Commander in Chief."

The question now is whether that letter means carte blanche for Raul, Fidel's longtime Defense Minister, to accelerate at least the economic if not the political reforms he's been hinting at in a series of speeches and minor policy adjustments over the last 18 months. As long as Fidel "is breathing and aware," says Latell, "Raul is still going to be somewhat constrained in what he can do." At the same time, he adds, Fidel's full-blown retirement "really does free Raul to do a lot more than he could in the provisional role. Now I think we'll see significant changes not just in style but in policy."

Latell foresees "cascading leadership changes" at the top involving younger army generals and other loyal raulistas, especially the military chief of staff, General Alvaro Lopez Miera, 63. Raul's son-in-law, Colonel Luis Alberto Rodriguez, is being groomed to take over the broad economic and business policy duties already held by the Revolutionary Armed Forces, including enterprises like the multibillion-dollar tourist concern Gaviota, which has helped keep Cuba afloat since the demise of its longtime benefactor, the Soviet Union.

Current Vice President Carlos Lage, 56, who shares Raul's less ideological economic policy vision, stands to tower over diminished fidelistas like Alarcon and Foreign Minister Felipe Perez Roque. Perez, 42, once considered a leader of the youthful fidelista hardliners known as los Taliban, has seen his stature particularly reduced under Raul  to the point that he was compelled late last year to endorse Cuba's acceptance of an international human rights accord, something Fidel had criticized as a violation of the island's sovereignty but which Raul had decided was necessary to begin thawing relations with the U.S. and the European Union. (Lest anyone think the move means greater respect for human rights in Cuba, however, consider that, shortly after the move, a group of dissidents were arrested and roughed up by police while seeking sanctuary in a church.)

Raul has called on Cubans in the past year to engage in more open debate  and he has made overtures to Washington, which maintains a 46-year-old trade embargo against Cuba. But he still has a reputation from his earlier years as Fidel's political enforcer, and few expect him to pursue any meaningful political reforms now or even when Fidel eventually dies. Instead, he is widely expected to push China-style economic liberalization, the kind of pragmatic programs, like opening to foreign tourism investment, that he has orchestrated in small, subtle increments to help Cuba survive postCold War. Cuba's epic economic inefficiencies are his pet peeve; and when he took the microphone last July 26 in Fidel's place, he gushed less about socialism's glories and railed more at the country's "deficiencies, errors and indolent bureaucratic attitudes." As a result, many expect one of his first major policy plays to be a wholesale reform of Cuban agriculture, which can't supply even staples like milk, with provisions like more profit-oriented farmers markets. That may well be followed by similar liberalization in service industries like tourism, where Cubans often make appreciably more than the nation's paltry $15-a-month average wage.